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SCIENCE

Observatories here and abroad are continuing to observe un­usual activity on the moon, raising to new heights the eager­ness of scientists for close‐up information on earth's natural satellite.

The latest report, published last week, also points up the hazard that will be faced by astronauts who land there. It concerns observations made from France's Pic du Midi Ob­servatory on a summit of the Pyrenees.

Twice in one night a large area of the moon glowed red, as recorded in photographs. It is thought that the glow was induced by bombardment of the lunar surface by high energy particles from a flare on the sun.

Generations of astronomers have looked upon the moon not only as lifeless but totally lack­ing in activity of any sort. On Oct. 26, 1956, Dr. Dinsmore Alter at the observatory on Mount Wilson in California ob­served what he took to be mis­tiness on the floor of the crater Alphonsus. This made little im­pression on the scientific world, but it aroused the interest of a Soviet specialist in spectroscopy, Dr. Nikolai A. Kozyrev.

The previous year Dr. Kozyrev had noticed peculiar properties in the spectrum of light from another lunar crater, Ari­starchus. He believed it was caused by luminescence of the surface material. Luminescence is “cold light,” as opposed to incandescence, and can be pro­duced in a variety of ways in­cluding exposure of a sub­stance to sunlight.

Dr. Kozyrev focused on Al­phonsus and, on Nov. 3, 1958, and Oct. 23, 1959, saw a bright spot whose spectrum suggested that carbon was being expelled from the moon's interior. The phenomenon was widely re­ported as an eruption, but it did not resemble a volcanic eruption in that there was no glow at night.

The report was at first ac­corded an astronomical cold shoulder. However, U.S. astron­omers who examined Dr. Ko­zyrev's spectra were impressed.

Last Oct. 29 those at the Lowell Observatory in Flagstaf, Arizona, who are editing moon maps for the Air Force, ob­served reddish spots near Aris­tarchus. They vanished within 20 minutes. One of the observers likened them to “a large pol­ished ruby gem.”

Again Observed

A month later, the same phe­nomenon was again observed. It consisted of an elongated red­dish area on the rim of the Aristarchus crater almost over­lapping one of the earlier spots. This time the observatory direc­tor phoned across Flagstaff to where Ohio State University's 69‐inch telescope has recently been installed.

The observer on duty at that site also saw the reddish spot before it faded. A striking fea­ture of these observations was that both occurred less than two days after sunlight returned, following the two‐week lunar night. This suggested the possi­bility that warming of the sur­face somehow released carbon from the interior.

The observations also came approximately when the moon was closest to the earth in its elliptical orbit. This is when the earth's gravity tugs at the lunar surface with maximum force. On June 4 and 5 the circumstances of the earlier observations will be repeated and attempts will be made to obtain photographs of the phenomenon.

The observations in France are described in the March issue of Sky and Telescope, published at the Harvard College Observa­tory. The report is by Drs. Zdenek Kopal and Thomas W. Rackham of the University of Manchester in England, With financial backing from the United States Air Force they have been studying the moon for a number of years at the Pic du Midi.

Twice, on the night of Nov. 1‐2, last year, they obtained photographs showing a large region near the Kepler crater to be glowing red. The observa­tion was part of a systematic search for luminescence on the moon.

Moon Glow

As early as 1946 it had been suggested by the Czech astrono­mer F. Link that the moon may glow, either under the influenee of ultraviolet light from the corona—the bright gas sur­rounding the sun—or because of bombardment by particles from solar eruptions.

He noted that the moon was strangely bright, even when passing through the earth's sha­dow during an eclipse. Because the moon has no air, ultraviolet rays strike it with undiminished intensity.

Drs. Kopal and Rackham ob­tained photographs in red light showing that twice, within a two‐hour period, the surface

Roughly eight and a half hours before these observations there had been small flares, or eruptions, on the sun. In recent years it has been found that certain flares shoot out bunches of high energy protons, or hy­drogen atom nuclei. These are directed toward the earth's mag­netic poles, where their impacts on the atmosphere produce radio blackouts.

If such proton clouds can be “seen” as they strike particular regions of the moon, the study of such events and their distri­bution in space would be greatly assisted. The 11‐year sunspot cycle is now at its minimum and flares are scarce. In the next five years solar activity will in­crease steadily and there should be many opportunities to verify the European observation.

At the same time traveling across the lunar surface will be­come more perilous, because of the increasing danger of bom­bardment with solar protons. If the European report is correct, it will be possible to observe such bombardments from the earth.